Exchange Mailbox Agent (M365) - Spool Copy

Hi ​@Erase4ndReuseMedia 

Good day!

Yes, technically a Storage Policy with Spool Copy enabled on the Primary Copy can be associated.
However, it is not recommended for Exchange Mailbox Agent backups.

Spool copy is not a persistent backup copy, It acts like a temporary staging area, Data is immediately aged/pruned once Aux Copy runs Data exists only until it is copied to another synchronous copy

For Exchange Mailbox Agent: Restore operations depend heavily on Primary copy

Commvault explicitly supports recovery from secondary copies when primary is unusable

Recommended Design (Best Practice)

For Exchange Mailbox Agent:

• Primary Copy → Standard (non-spool) copy with retention
• Secondary Copy → Long-term or DR copy

Reference

Recovering Data From Secondary Copy for Exchange Mailbox

That is disappointing. We are really struggling with our current configuration. 

We are performing mailbox backups solely for Disaster Recovery purposes, with Access Nodes and Index Servers residing on-premises, and the associated MediaAgents and backup storage hosted on a separate cloud provider. With the lacklustre performance, we are finding our long-running archive operations are prone to intermittent communication issues.  

With no option for direct communication between Azure/M365 and our second cloud provider, and no appetite to host the entirety of the Mailbox backups on-premises, Spool Copy would have been an ideal alternative.

With all of the issues we’ve been having with the Mailbox Agent and accompanying Index Server, we are struggling to find any redeeming features in this solution.